How much does a garage conversion cost in Teesside? (2026)
A garage conversion in Teesside costs £6,000 to £12,000 for a part conversion, £10,000 to £18,000 for a full single garage conversion, £12,000 to £20,000 with an en-suite or as a kitchen extension, and £15,000 to £30,000 for a detached garage in 2026.
Why garage conversions are the cheapest room you can add
The structure already exists. Foundations, walls and a roof are the most expensive parts of any new living space, and a garage conversion gets all three for free. That is why a full conversion costs £10,000 to £18,000 while a single-storey extension of the same floor area costs £30,000 to £45,000 on Teesside. Per square metre of new living space, nothing else comes close.
The money in a conversion goes on making an outbuilding-grade structure perform like a room: the floor build-up, insulation, damp proofing, the new front wall, electrics and heating, and building control sign-off.
What actually moves the price
The floor
Garage slabs usually sit lower than the house floor and were rarely laid with a damp-proof membrane. Budget £1,500 to £3,000 for a proper floor build-up: membrane, insulation and screed, or a suspended timber floor, matched to house level. A quote that skips this produces a room with a step down that feels cold forever.
The front wall
Closing the garage door opening with a proper cavity wall and matched window costs £2,000 to £4,000 depending on brick matching and glazing. This is the part of the job the street sees, and the difference between "converted garage" and "always was a room".
Plumbing
Adding an en-suite or utility adds £4,000 to £6,000, dominated by how far the new drainage has to run to reach the soil stack. Kitchens cost more again once units and appliances are in.
The existing structure
Integral garages under a bedroom are usually the simplest. Single-skin detached garages, sectional concrete garages and anything with a tired roof need more work, and an honest quote tells you that before you start, not after.
How to judge a quote
Four things separate a real quote from a number on the back of a card: the floor build-up specified in writing, insulation values stated rather than "fully insulated", building control fees included, and the front wall described in materials, not adjectives. If any of the four is missing, ask why. Prices on this page are reviewed quarterly and reflect what Teesside contractors actually charge, not national averages.
| Conversion type | Typical price | Time on site | Notes |
|---|---|---|---|
| Part conversion | £6,000–£12,000 | 2–3 weeks | Keeps front storage |
| Full conversion (single) | £10,000–£18,000 | 2–4 weeks | The Teesside standard |
| Garage to home office | £8,000–£15,000 | 2–3 weeks | Spec-led: sockets, data, light |
| Bedroom + en-suite | £12,000–£20,000 | 4–6 weeks | Plumbing adds £4k–£6k |
| Kitchen extension (knock-through) | £12,000–£20,000 | 4–6 weeks | Plus the kitchen itself |
| Detached garage | £15,000–£30,000 | 4–8 weeks | Services trenched from house |